Ear probe for use in closed-loop caloric irrigation

ABSTRACT

An ear probe for use in closed-loop caloric irrigation including a manifold and balloon, the manifold conducting fluid flow into and out of the balloon concentrically, the balloon being a one-piece, elongate, cylindrical member formed from an elastic material and having open and closed ends and sections of different diameters and thicknesses. One section is inflatable, having a small diameter and a minimum thickness to permit insertion into the ear canal and inflation into contact with the inner ear. Another section has a relatively large outside diameter and a substantial thickness so as to contact the exterior ear and limit movement of the balloon into the ear canal. An intermediate section has a relatively small diameter to permit insertion into the ear canal and an increased thickness to prevent inflation thereof, the intermediate section providing a return flow channel for fluid conducted through the balloon.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of application Ser. No.760,178, filed Jan. 17, 1977 now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an ear probe for use in closed-loopcaloric irrigation and, more particularly, to an improved probeincluding a disposable silicone rubber balloon for use with caloricirrigation apparatus.

2. Description of the Prior Art

The human species has evolved and developed an elaborate balance systemto allow for proper relationship between its surroundings and an erectposture. The system is a complicated one, requiring integration ofinformation from the visual system, the vestibular system, and theskeletal-muscular system.

For a patient complaining of dizziness and impaired balance, a disordercan exist in any of these systems. To determine the source of thedisorder, many different tests are performed. In addition to thespontaneous nystagmus and postual reflex tests, a complex recordingtechnique has been developed called electronystagmography (ENG). ENGprovides for a permanent objective recording, obtained in a relativelystandardized manner, of responses from the vestibular system.

In order to perform adequate tests utilizing ENG, the vestibular systemmust be stimulated to create the condition of dizziness and impairedbalance. It has been determined that proper stimulation may be achievedby adding heat to or taking heat away from the inner ear. It is for thispurpose that several caloric irrigators have been developed.

A conventional caloric irrigator consists of a fluid reservoir, a fluidpump, a heating and cooling system, and a conduit for conducting fluid,pumped by the pump, from the reservoir, through the heating and coolingsystem, to a probe insertible into the ear canal. While caloricirrigators are widely used, existing equipment has many disadvantagesassociated therewith. A basin or towel is required to catch the waterflowing out of the ear, making the procedure difficult and awkward. Theprocedure requires trained personnel and it is virtually impossible tostimulate both ears simultaneously, which many experts say is anecessity for a meaningful test. Such a procedure is not applicable inthe case of a patient with a perforated eardrum since the water willflow through the perforation. It is also difficult to measure a fixedstimulation parameter such as temperature, fluid volume, and flow rate.

To solve the above problems, it has been proposed by researchers in theDepartment of Otorhinolaryngology, School of Medicine, Keio University,Tokyo, Japan, to provide a closed-loop channel for conducting fluid fromthe reservoir to the ear and back to the reservoir. The proposed systemconsists of a water tank with a stirrer, a heating and cooling system, atemperature control system, a pump system with a timer, and a siliconeear canal balloon. The silicone balloon is inserted into the auditorycanal and is made to adhere tightly to the canal wall by the pressure ofthe water as it is pumped from the reservoir, into the balloon, and backto the reservoir. Heat transfer to the ear canal is achieved through thewall of the balloon. Since the water does not directly contact the ear,the system can be used even with a perforated eardrum. Unilateral orbilateral simultaneous stimulation can be performed and the variousparameters can be readily controlled.

Even with the above advantages of a system using an inflatable balloon,several problems still exist with the proposed apparatus. The balloon ofthe proposed system is a one-piece, molded part having an inlet and anoutlet that are positioned side by side. This makes the balloon overlylarge, preventing its use with very small or partially obstructed earcanals. Furthermore, the one-piece construction is complex and expensiveand the entire unit must be replaced periodically.

Generally speaking, the purpose of a probe is to maintain a precisetemperature, for a given time, in the ear canal, as close to the eardrum as possible. Ear canals vary in size depending on age and physicalstructure of a patient so it is necessary to construct a probe that canbe used in all subjects, thereby eliminating error by a technician. Tomaintain a given temperature in the ear canal, it is necessary tomaintain a given fluid flow. Since the dimensions should be held to aminimum and flow to a maximum, the construction of a total probe is thekey to feasibility.

The ear canal is sensitive to foreign objects. Therefore, the probe mustbe soft and of low mass so that placement can be done with the leastamount of trauma to the patient. For sterilization purposes, the portionof the probe that goes into the ear should be replaceable. The probeconstruction should define probe placement relative to the ear so thattests are repeatable. Repeatability of probe placement in the ear canalis also important because total heat transfer is dependent on ballooncontact. A probe satisfying all of these requirements has beenunavailable heretofore.

SUMMARY OF THE INVENTION

According to the present invention, these problems are solved in amanner unknown heretofore by the provision of a unique ear probe for usein a closed-loop caloric irrigator. The present probe includes amanifold and an inflatable balloon adapted to be placed in the ear canaland to have a fluid such as water pumped therethrough for stimulatingthe ear canal wall and the ear canal. With the present probe, the fluidflow into and out of the balloon is concentric. This allows the tip ofthe probe to have an extremely small diameter, providing greaterapplicability with individuals with small or partially obstructed earcanals. The probe is not only smaller, but simpler and less costly thanprior probes, permitting replacement of the balloon only and not theentire probe. Use of a concentric in-flow and out-flow system alsoprevents partial collapse of the balloon because of the ear creating arestriction.

The present probe is soft and of low mass so that placement can be donewith the least amount of trauma to a patient. The hoses leading to theprobe are small and lightweight and are attached to a right angle to theprobe to assure a minimal total mass to be handled. The balloons areeasily removed from the manifold and are held in place by the elasticityof the balloon.

The present balloon contains three sections. A first section, theretainer section, at the open end of the balloon, is used as a stop forprobe placement. This permits a repeatable placement of the probe in theear canal. An intermediate section has a heavier wall than theinflatable section and will not inflate. It serves as an extension forthe return flow of fluid. The inflatable section, at the closed end ofthe balloon, is very thin, assuring good heat transfer and the abilityto conform to irregularities and shapes of different ear canals. Theinflatable section has a slightly heavier wall at the tip, reducing therisk of damage during insertion and reducing the likelihood of breakagein the direction of the ear drum.

Briefly, the present probe includes a manifold and a balloon, themanifold conducting fluid flow into and out of the balloonconcentrically, the balloon being a one-piece, elongate, cylindricalmember formed from an elastic material and having open and closed endsand sections of different diameters and thicknesses, the balloonincluding a first, inflatable section defining the closed end thereof,the first section having a relatively small diameter to permit insertioninto the ear canal and a minimum thickness to permit inflation thereofinto contact with the inner ear, a second, non-inflatable sectionintermediate the open and closed ends thereof, the second section havinga relatively small diameter to permit insertion into the ear canal andan increased thickness to prevent inflation thereof, the first andsecond sections being approximately equal in length, and a third,non-inflatable section defining the open end thereof, the third sectionhaving a relatively large outside diameter and a substantial thicknessso as to contact the exterior ear and limit movement of the first andsecond sections of the balloon into the ear canal.

OBJECTS

It is therefore an object of the present invention to provide an earprobe for use in a closed-loop caloric irrigator forelectronystagmography.

It is a further object of the present invention to provide an ear probeincluding a manifold and an inflatable balloon adapted to be placed inan ear canal.

It is a still further object of the present invention to provide an earprobe for use in a closed-loop caloric irrigator in which dimensions areheld to a minimum and flow to a maximum.

It is another object of the present invention to provide an ear probewhich permits maintenance of a precise temperature, close to or at theear drum, regardless of the physical structure of a patient.

Still other objects, features and attendant advantages of the presentinvention will become apparent to those skilled in the art from areading of the following detailed description of the preferredembodiment constructed in accordance therewith, taken in conjunctionwith the accompanying drawings wherein like numerals designate likeparts in the several figures and wherein:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a probe constructed in accordance withthe teachings of the present invention for use in a closed-loop caloricirrigator;

FIG. 2 is a side elevation view of the probe of FIG. 1 shown inoperative, inflated position in the ear canal;

FIg. 3 is a longitudinal sectional view of the probe of FIG. 1; and

FIG. 4 is a sectional view taken along the line 4--4 in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings, there is shown a probe, generallydesignated 10, for use with a caloric irrigator for unilateral orbilateral stimulation for use in ENG. For a complete description of aclosed-loop caloric irrigator, which is not the subject of the presentinvention, reference should be had to my copending U.S. patentapplication Ser. No. 760,178, filed Jan. 17, 1977 and entitledClosed-Loop Caloric Irrigator.

For the purposes of the present invention, a caloric irrigator of thetype described in my prior application includes a unitary cabinet havinga front panel on which is mounted the various gauges and controlsrequired. Such a caloric irrigator is of the general type previouslydescribed for pumping, for a predetermined time, a fluid, such as water,the temperature of which is accurately controlled, to probe 10insertable in the ear canal 11 of a patient 12.

Housed within such unitary cabinet is a fluid reservoir which mayconsist simply of a cylindrical tank having at least one inlet and atleast one outlet the outlet, of the reservoir being connected to theinlet of a pump, the operation of which is controlled by an electricaltimer. Where the irrigator is designated for bilateral simultaneousstimulation, the output of the pump is typically connected to a conduithaving four branches, each of which includes an identical valve, thevalves being manually or electrically operated by switches mounted onthe front panel of the cabinet. Two of the valves control the flow offluid into a first heat exchanger for heating the fluid passingtherethrough. The other two valves control the flow of fluid into asecond heat exchanger for cooling the fluid passing therethrough.

In a caloric irrigator for bilateral simultaneous stimulation, twoprobes 10 would be utilized for effecting heat transfer between thefluid in the reservoir and the ear canals 11 of patient 12. Each probe10 has an inlet 13 and an outlet 14. The inlets 13 of probe 10 areconnected to the outlets of the heat exchangers by lengths of tubing 15.Outlets 14 are connected by lengths of tubing 16 to the inlets of thereservoir.

Generally speaking, the reservoir, the pump, the valves, the heatexchangers, and the probes are interconnected by means of conduit means,preferably plastic tubing, such as tubing 15 and 16, forming aclosed-loop channel whereby the pump pumps fluid from the reservoirthrough one of the heat exchangers and the probes back to the reservoir.Whether hot or cold water is used is determined by which valves areopened and closed and which heat exchangers are used.

Referring now primarily to FIGS. 3 and 4, the construction of probe 10will be described in detail. Specifically, probe 10 includes a manifold,generally designated 20, and a balloon, generally designated 40.Manifold 20 includes an elongate cylindrical body 21 having a centralaxial channel 22 therein. At one end of body 21, channel 22 is connectedto a lateral channel 23 which receives one end of a sleeve 24 whichprovides the fluid inlet 13 for manifold 20. Sleeve 24 is connectable tofluid inlet line 15. Sleeve 24 conducts fluid from inlet line 15 intochannel 23 and channel 22 and then into one end of an elongate sleeve 25which terminates in channel 22 and extends through and out of the otherend of body 21.

Adjacent the other end of body 21 is an enlarged axial channel 27 whichis coaxial with channel 22 and has a diameter greater than the diameterof channel 22. Channel 27 is in fluid communication with a lateralchannel 29 which receives one end of a sleeve 30 which functions asfluid outlet 14 of manifold 20. Sleeve 30 is connectable to fluid outletline 16. Thus, sleeve 30 conducts fluid from channel 27 into fluidoutlet line 16.

Channel 27 receives one end of an elongate sleeve 31 which is coaxialwith sleeve 25, sleeve 25 extending entirely through sleeve 31 whichextends slightly beyond the other end of body 21. The outside diameterof sleeve 25 is less than the inside diameter of sleeve 31 to permitfluid flow therebetween. The end of sleeve 25 which extends beyond body21 of manifold 20 receives one end of an elastic tube extension 32 whichis preferably made from silicone, for reasons which will appear morefully hereinafter.

According to the present invention, probe 10 incorporates balloon 40which is preferably made from silicone rubber so as to be highly elasticand capable of repeated cycles of expansion and contraction. Balloon 40is designed so that probe 10 may maintain a precise temperature, for agiven time, in ear canal 11, as close to ear drum 17 of patient 12 aspossible. For sterilization purposes, balloon 40 is readily removablefrom manifold 20 so that balloon 40 can be discarded.

More specifically, balloon 40 is a one-piece, elongate, cylindricalmember having an open end and a closed end. Preferably, balloon 40 has auniform inside diameter throughout the length thereof and includessections 41, 42, and 43 of different outside diameters and differentthicknesses. Section 41 of balloon 40 is the inflatable balloon sectionwhich defines the closed end of balloon 40. Section 41 has a relativelysmall outside diameter to permit insertion into ear canal 11. Section 41also has a minimum thickness to permit inflation thereof into contactwith the inner ear. This assures good heat transfer and also ensuresthat balloon section 41 will conform to the irregularities and shapes ofear canal 11.

On the other hand, balloon section 41 has a slightly increased wallthickness at the tip 44 thereof to reduce the risk of damage duringinsertion into ear canal 11 and making it less likely that balloonsection 41 will break in the direction of ear drum 17. According to thepresent invention, balloon section 41 preferably has an inside diameterof 3.7 mm, a wall thickness of 0.15 mm, an outside diameter of 4 mm, anda length of 13 mm.

The open end of inflatable section 41 is integral with a shaft section42 which is non-inflatable and positioned intermediate the open andclosed ends of balloon 40. Section 42 has a relatively small diameter topermit insertion into ear canal 11 but an increased wall thickness toprevent inflation thereof. Section 42 serves as an extension for thereturn flow of fluid through balloon section 41. If the thicknesses ofsections 41 and 42 were the same, it would be very likely that section42 would inflate outside of ear canal 11 and break. As can be seen froman inspection of FIG. 2, section 42 does not inflate, all the inflationof balloon 40 being in section 41. According to the present invention,section 42 preferably has an inside diameter of 3.7 mm, a wall thicknessof 0.4 mm, an outside diameter of 4.5 mm, and a length of 13 mm. It cantherefore be seen that the lengths of sections 41 and 42 areapproximately equal, again ensuring that there is no inflation ofballoon 41 outside of ear canal 11.

Balloon 40 includes a third, non-inflatable, retainer section 43defining the open end thereof, retainer section 43 having a relativelylarge outside diameter and a substantial thickness so as to function asa stop for proper placement. That is, as shown in FIG. 2, the outsidediameter of retainer section 43 is such that it will contact theexterior ear and limit movement of sections 41 and 42 of balloon 40 intoear canal 11. Since total heat transfer is dependent on balloon contact,it is important that placement in ear canal 11 be repeatable andretainer section 43 ensures that this is the case. Furthermore, retainersection 43 may be fitted onto sleeve 31 of manifold 20 and is held inposition thereat by the elasticity of the material of balloon 40.According to the present invention, section 43 preferably has an insidediameter of 3.7 mm, an outside diameter of 9.5 mm, and a length of 4 mm.

As can be seen in FIGS. 2 and 3, tube extension 32 assures a good liquiddelivery close to tip 44 of inflatable section 41 where irrigation ismost important. Furthermore, when inserting probe 10 into ear canal 11,extension 32 prevents balloon 40 from doubling over.

As will be apparent from an inspection FIG. 3, fluid conducted tomanifold 20 by inlet line 15 flows through sleeve 25 and extension 32into inflatable section 41 of balloon 40. Such fluid then passes betweentube extension 32 and shaft section 42 of balloon 40, between sleeves 25and 31, and through channel 27 and flows via sleeve 30 into fluid outletline 16.

It can therefore be seen that according to the present invention, theproblems encountered with previous probes for use in a closed-loopcaloric irrigator are solved by the provision of a unique probe 10.Probe 10 includes a manifold 20 and an inflatable balloon 40 adapted tobe placed in ear canal 11 and to have a fluid such as water pumpedtherethrough for stimulating ear canal 11. With probe 10, the fluid flowinto and out of balloon 40 is concentric. This allows sections 41 and 42of balloon 40 to have a small diameter, providing greater applicabilitywith individuals with small or partially obstructed ear canals. Probe 10is not only smaller, but simpler and less costly than prior designs,permitting replacement of balloon 40 only and not the entire probe 10.Use of a concentric in-flow and out-flow system also prevents partialcollapse of balloon 40 because of the ear creating a restriction.

Probe 10 is soft and of low mass so that placement can be made with theleast amount of trauma to a patient. The hoses leading to manifold 20are small and lightweight and are attached to body 21 at a right angleto assure a minimal total mass to be handled. Balloon 40 is easilyremovable from manifold 20 and is held in place by the elasticity ofballoon 40.

While the invention has been described with respect to the preferredphysical embodiment constructed in accordance therewith, it will beapparent to those skilled in the art that various modifications andimprovements may be made within departing from the scope and spirit ofthe invention. Accordingly, it is to be understood that the invention isnot to be limited by the specific illustrative embodiment, but only bythe scope of the appended claims.

I claim:
 1. An ear canal balloon comprising:a one-piece, elongate,cylindrical member formed from an elastic material and having open andclosed ends and sections of different diameters and thicknesses, saidmember including:a first section defining the closed end thereof, saidfirst section having a relatively small diameter to permit insertioninto an ear canal and a minimum thickness to permit inflation thereofinto contact with the inner ear; a second section intermediate the openand closed ends thereof, said second section having a relatively smalldiameter to permit insertion into said ear canal and a thickness whichis greater than the thickness of said first section by an amountsufficient to prevent inflation thereof in use, said first and secondsections being approximately equal in length; and a third sectiondefining the open end thereof, said third section having a relativelylarge outside diameter and a substantial thickness so as to contact theexterior ear and limit movement of said first and second sections ofsaid balloon into said ear canal.
 2. An ear balloon according to claim1, wherein said member is made from silicone rubber.
 3. An ear balloonaccording to claim 1 or 2, wherein said first, second and third sectionshave the same inside diameter.
 4. An ear balloon according to claim 1,wherein said first section has a slightly increased wall thickness atthe tip thereof.
 5. An ear balloon according to claim 1, wherein saidfirst section has an inside diameter of approximately 3.7 mm and a wallthickness of approximately 0.15 mm.
 6. An ear balloon according to claim5, wherein said second section has an inside diameter of approximately3.7 mm and a wall thickness of approximately 0.4 mm.
 7. An ear balloonaccording to claim 6, wherein said third section has an inside diameterof approximately 3.7 mm and an outside diameter of approximately 9.5 mm.8. An ear balloon according to claim 7, wherein said first, second, andthird sections have lengths of approximately 13 mm, 13 mm, and 4 mm,respectively.
 9. An ear probe for use in closed-loop caloric irrigationcomprising:a manifold including:an elongate cylindrical body having aside wall, an open end and a closed end and first and second coaxialchannels extending therethrough; and inlets and outlets extendinglaterally through said side wall of said body into fluid communicationwith said first and second channels, respectively; and a one-piece,elongate, cylindrical, ear canal balloon formed from an elastic materialand having open and closed ends and sections of different diameters andthicknesses, said open end of said balloon being removably connectableto said open end of said manifold body, said manifold conducting fluidinto and out of said balloon.
 10. An ear probe according to claim 9,wherein said manifold body has a central axial channel connected to saidoutlet and a sleeve extending through said channel and connected to saidinlet, said open end of said balloon being connected to said body ofsaid manifold and said sleeve extending into said balloon.
 11. An earprobe according to claim 9 or 10, wherein said balloon comprises:a firstsection defining the closed end thereof, said first section having arelatively small diameter to permit insertion into an ear canal and aminimum thickness to permit inflation thereof into contact with theinner ear; a second section intermediate the open and closed endsthereof, said second section having a relatively small diameter topermit insertion into said ear canal and a thickness which is greaterthan the thickness of said first section by an amount sufficient toprevent inflation thereof in use, said first and second sections beingapproximately equal in length; and a third section defining the open endthereof, said third section having a relatively large outside diameterand a substantial thickness so as to contact the exterior ear and limitmovement of said first and second sections of said balloon into said earcanal.